Objection after acceptance of gifted land.

Hi, I am Protyush Das, from Siliguri. My grandfather has 4 children i.e. 2 sons and 2 daughters. After being migrated from Bangladesh about 45 years ago grandfather started to live on a plot of 4 katha. After immature death of my Grandfather, my father, who is the eldest of all children became mature, the land for the first time becomes in name of him. He took all the responsibilities and burden of whole family and then made a house on 2.5 katha. That time the family was joined. After 30 years the relationship between father and uncle declined because of my aunt and to get rid of this bad relationship my father gifted 1.5 katha land along with 3 roomed house to my uncle. After 5 years of partitioning my Uncle is raising the objection that, Why the land not divided in 2 equal part? They are going to take legal step for it. The 2 sisters are not involved in this land matter and my father is bearing the whole responsibility of my Grandmother who lives with us. I want to know is that possible to raise objection after 5 years of the acceptance of the gifted land and what should be our step against this. Please help us.